Last Modified: Monday, February 4, 2013 at 2:03 p.m.

John Alan Mellquist, 53, faces a second-degree murder charge in the death of Anneliese Schweickardt. (Provided by Sarasota County Sheriff's Office)

Sarasota County sheriff's deputies arrested Schweickardt's former tenant, John Alan Mellquist, on Friday. He was charged with second-degree murder and remains held in the county jail without bail.

Schweickardt was a German citizen who lived in the United States on a tourist visa. She had no immediate family in this country, but kept in routine contact with a childhood friend in Germany. She also traveled annually to maintain her tourist visa status.

The investigation into her death began as a missing person case in October 2003, when her friend reported that she stopped receiving regular contact from Schweickardt, who was 69 at the time.

Schweickardt was in the process of evicting Mellquist, who rented a room in her Sarasota home.

When initially interviewed by investigators, Mellquist gave differing accounts of her possible whereabouts. It was later learned that he had forged and cashed checks from her bank account, and used her vehicle after she had disappeared.

Detectives and forensic technicians conducted an exhaustive search of the victim's home in 2003. They found signs of a violent encounter inside the home, including significant blood stain evidence that indicated she was likely murdered.

Investigators found evidence blood had been mopped off of the kitchen floor. A significant amount of blood had pooled, leaked through the linoleum and stained the concrete beneath. They also noted that blood had been splashed onto the kitchen cabinets, stove and a refrigerator. They found more blood in a laundry room, and on a mop, which they believe was used to clean the kitchen of blood. Mellquist's fingerprints were found on the mop handle.

They found blood and drag marks leading across the garage floor, which ended where a vehicle would likely have been parked.

These discoveries, coupled with what detectives believe were lies during their questioning of Mellquist, led them to suspect that he had killed her.

Schweickardt's body has never been located despite a comprehensive search of the area near her home in 2003. Absent the body, and with no immediate family such as children, it took years for investigators to build a DNA profile of the victim from personal items left in the residence.

Advancement in DNA testing and the capabilities of the Florida Department of Law Enforcement lab have led detectives to this point in the investigation.

According to reports, there was sufficient evidence to arrest Mellquist now. Sheriff's detectives conferred with the State Attorney's Office throughout this investigation, and prosecutors agreed with the timing of the arrest.

Detectives have kept track of Mellquist over the years since Schweickardt's death, and located him living in a tent in a wooded area near Ortiz Boulevard and U.S. 41 in Warm Mineral Springs.

Court records show Mellquist has been previously arrested in Sarasota County on charges of disorderly intoxication, battery, soliciting a prostitute and criminal damage.

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